Process for producing printing-plates.



L. 1. HER TLIN PROCESS FORPRODUCING PRINTING PLATES,

APPLICATION FILEVD Nov.20, 1915. i v

' Patented Aug. 20,1918

WITNESSES INVENTOR STATFd LOUIS JOHN HERTLT'N, OF BROOKLYN, NEW YORK.

PROCESS FOR PRODUCING PRINTING-PLATES.

To all whom it may concern:

Be it known that 1, Louis J. HERTLIN, a citizen of the United States, and a resident of New York, in the county of Kings, borough of Brooklyn, and State of New York, have invented a new and useful Process for Producing Printing-Plates, of which the following is a specification.

My process relates to the production of printing plates used for printing diiferent colors, and the object is to devise a method whereby such plates may be produced wit-hout the need of skilled labor and at comparatively little cost. The process is particularly suitable for printing exact reproductions of designs of linoleums, oil-cloth, and the like.

My process while photo-lithographic does not requirea camera, a master or key sheet of transparent material being provided upon .which the outlines or border lines of the de-' sign are formed, as by printing in a press or otherwise; this sheet being used in the manner of a photographic negative for making prints on special plates such as zinc or aluminum or on stone. In my process the master sheet is altered for each plate after the photographic print has been made. The treatment of the plate is as usual.

In the appended drawing forming a part of this specification, in which like reference characters refer to like parts in each of the views, A

Fi ure 1 represents the master transparent sheet'which is employed inthe formation of all the color plates.

Fig. 1 is a positive photographic print madegfrom the master sheet upon a transparent sheet.

Fig. 1 is a view of the border line plate.

Fig. 2 is a reversed view of the master sheet with certain spaces blocked out to form one color plate.

Fig. 2 is a view of the color plate made by means of the master sheet as blocked out in Fig. 2.

Fig. 3 is a reversed view of the master sheet with certain spaces blocked out to form another color plate.

Fig. 3 is a view of the color plate made by means of the master-sheet as blocked out 'in Fig. 3.

Fig. t is a reversed view of the master sheet with certain spaces blocked out for another color plate. v

Fig. 4% is a view of the color plate made Specification of Letters Patent.

Patented Aug. 20, 19th.

Application filed November 20, 1915. Serial No. 62,579.

by means of the master sheet as blocked out in Fig. 4.

Referring to the drawings, 5 is a sheet of transparent material such as celluloid on which is printed or otherwise provided a straight line design as common in designs of linoleum and oil-cloth. As shown in Fig. 1, the lines 6 forming the design run diagonally on the sheet. These lines as soon as impressed upon the sheet are covered with an opaque powder, preferably of a readily distinguishable color, as for example bronze powder. This renders the lines of ink im penetrable to light.

After the powdered ink has dried, the

similar spaces defined by the lines 6 are colored identically for identification purposes, and as shown, the central space R is colored red. The triangular spaces B dominatin the right angles of the square are colore blue and the spaces Y dominating the sides of the square are colored yellow. All these colors are transparent, and in view of the fact that the lines 6 are of suiiicient width, the colors may be applied by unskilled labor, as no care is required, the lines 6 presenting sufficient mar in for that purpose.

To obtain the desired negative from this plate, the same is turned face down and some opaque in the form of paint, preferably such as water colors, is applied to the transparent spaces which are to be made impenetrable to light. As shown in Fig. 2, the transparent sheet 5 has been blocked out with opaque paint in the spaces B and Y, in other words, leaving only the square R transparent to light. Again, in View of the width of the lines 6, the application of the opaque paint can be readily done by unskilled labor.

When a zinc or aluminum plate which has been coated with a substance sensitive to light is exposed through ,the sheet 5, as shown in Fig. 2, and then etched, a plate 8 such as shown in Fig. 2 will result. The

embossed part ofthe plate will be R This plate 10 will result (see Fig. 3 which has an embossed surface B t form the blue printing plate. Ir the paint is washed off from the bottom surface of the sheet 5 and the same coated With opaque paintto render the spaces R and B impeno treble to light and leaving; the spaces 1 penetrable to light (see Fig. l) and then a zinc or aluminum plate is sensitized and exposed to light through said sheet shown in Fig. l, a printing plate 12 (see Fig. i will result which has raised surfaces Y which is to form the yellow printing; plate. lVhen a sheet of paper has been printed on by the three plates 8, and 12, the colors are in the respective spaces as indicated in Fig. 1 but the lines 6 are not produced thereon. The surfaces corresponding these lines are unprinted by reason of the fact that the printing; surfaces R B and 1' do not touch each other, and it is necessary to make another printing plate for 1 these lines.

in Fig. 1 is shown a supplementary shee or transparent material 13 previously sensi-' tized and exposed through the sheet 5 in its normal condition. The resulting positive presents the line 6 clear and the color spaces opaque; and when the plate iprerionsly sensitized has been exposed through the sheet 13 the nnetched lines 6 form the printingsurface of said printing plate, and hyineans of which any distinctive color may be printed upon the paper already having the three'color impression thereon.

Becausethe colors may he applied h skiled labor and because oi the 1m); since the opaque is applied upon the or the transparent n c t, may be used repeat i ut the design on the economical process i opaque paint fully descrineo my process, What to secure by et- 1 ciaii ters Pat nt is:

1. The process for producing printing lates which consists in impressing a design ll l1 ink upon the face of a transparent 'heet dusting upon the ink a powder adapt d to render the covered by ink impenetrable so light, then blocking; ont those parts oi the sheet which are to be rendered inipenetrable to light oy'nieans oi Washable applying the same to the hack of the sheet, and using the so prepared sheet as a negative for producing a printing plate.-

2. The process for producing printing plates which consists in impressing with ink a design upon the face of a transparent sheet, the lines 015 t 1e design bein of substantial width, covering the ink or the design nitha powder which renders the ink covered part of the sheet impenetrable to light, applying a Washable opaque substance to the hack of the sheet in the desired spaces'ontlined by the design, then producing a printing plate from the so formed negatiw then removing the opaque substance from-the each face of said sheet, and applying similarly Washable opaque substance to the back in diii erent spaces within the spaces outlined-h; the design and producing pr'ntinp' plate fro-in the so formed negative.

ion in the presence 

